Floor designs provided with facilities allowing for the removal of pig excrement are already known. Such facilities usually consist of a trap which is formed in the floor, and which is designed to be raised when required in order for the excrement to be evacuated. When the floor designs fitted with such evacuation facilities are installed, for example, in birthing boxes, they may sometimes present a hazard for sows and piglets. The trap, when open, may cause the piglets to fall through, or may injure the lower members of sows. In addition to this, such techniques for the evacuation of excrement require daily manual intervention by humans in order to open them.
An attempt has already been made to remedy these disadvantages in part, by using a grating arrangement, as described in German Application DE-A-4 010 817. A lateral section pivots in relation to one of its edges, and thus forms an orifice. The orifice which is created in this manner, on the lateral edges of the grating, avoids the risk of injury to the sows injuring their lower members, since they do not reach as far as this point. However, this kind of a structure does not prevent piglets from falling through if the lateral section is not repositioned in its closed position.